86 f150 Turn Indication issues.
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5th Wheeling
Joined: Dec 2024
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86 f150 Turn Indication issues.
Hey guys ive got a 1986 f150. 4.9L Straight Six , 2wd , 3spd auto. My issue is that when i turn right , it indicates fine. Left however , only makes the left brake light come on SOLID , and nothing up front. I already tried replacing the turn signal switch ( didnt install it but plugged a new one in to confirm it wasnt the issue , and it still did the same flashing issue.). I cannot think of anything that would cause only the left to not work , any ideas guys ?
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From: Virginia
The flasher works on heat. The heat is generated by the current flowing to the proper amount of bulbs in the circuit. If a bulb is blown or a connection is bad and the bulb is not working, then the flasher will not have enough bulb load to blink and will just stay on solid.
Repair the front light that is not working, and that will fix it. I would try a new bulb socket and splice that in place.
Repair the front light that is not working, and that will fix it. I would try a new bulb socket and splice that in place.
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5th Wheeling
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I replaced both front head light assemblies and the turn bulb. still having the same issue Im gonna try again tommorow and replace the turn signal bulb connector its kinda turning into dust.
Last edited by birdthedude; Dec 27, 2024 at 09:26 PM.
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From: Virginia
A testlight is what you need for troubleshooting this. Probe the correct front left turn wire with the testlight and the lights may start blinking. The testlight may present enough load to make the flasher blink.
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5th Wheeling
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It's curious that the front left flashes on the emergency flasher switch but not on the turn signal switch. If the bulb socket is crispy then change it out. A wonky ground could account for blinking through the Hazzard switch but not through the turn signal switch. More bulbs means more heat on the Hazzard flasher. Could be a weak flasher unit on the turn signal side. There are two flashers one for each circuit. The turn signal flasher is the front side mounted one.
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5th Wheeling
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hold on , is there supposed to be a dual post bulb ? Orielly sold me a single contact bulb with only one filament Looking at the diagram it seems it wants a double filament. When i replaced the other turn it too looked like a brand new ish bulb. So im thinking the OG owner replaced it , bought the wrong bulb that doesnt close the circut fully and now we're here. That even possible ? Cuz the circuit diagram would leave me to belive it is
Last edited by birdthedude; Dec 28, 2024 at 10:28 AM.
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Well played! No matter the problem, always blame the previous owner:
Back to the turn signal problem, however it happened. Please follow the link to the troubleshooting guide, in post #4 above. It explains more than you ever wanted to know about your turn signals, including the special dual-filament bulbs, the two types of flasher units and their locations, etc.
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5th Wheeling
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Well played! No matter the problem, always blame the previous owner:
https://www.youtube.com/watch?v=c3sOuEv0E2I
Back to the turn signal problem, however it happened. Please follow the link to the troubleshooting guide, in post #4 above. It explains more than you ever wanted to know about your turn signals, including the special dual-filament bulbs, the two types of flasher units and their locations, etc.
https://www.youtube.com/watch?v=c3sOuEv0E2I
Back to the turn signal problem, however it happened. Please follow the link to the troubleshooting guide, in post #4 above. It explains more than you ever wanted to know about your turn signals, including the special dual-filament bulbs, the two types of flasher units and their locations, etc.
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From: Tolland, CT
Aren't these signal bulbs 1157's ? and 1157A if it needs to be yellow ? It's been decades since I've had to mess with them. I seem to recall a 1034 bulb number too. I'll have to ask google.
https://www.google.com/search?q=1034...t=gws-wiz-serp
1157,
https://www.google.com/search?q=1157...t=gws-wiz-serp
For the indicator in the dash, I'm sure that bulb is burnt out, as both of mine have been for many years.
https://www.google.com/search?q=1034...t=gws-wiz-serp
1157,
https://www.google.com/search?q=1157...t=gws-wiz-serp
For the indicator in the dash, I'm sure that bulb is burnt out, as both of mine have been for many years.